Optical output module, vehicle including same, and control method therefor

ABSTRACT

An embodiment relates to an optical module which comprises: a light transmitting unit for emitting a plurality of beams to a scanning area so as to scan the scanning area; and a light receiving unit for measuring information on an object located inside the scanning area, using backward light which is reflected and returned from the object after the emitted beams hit the object, wherein the scanning area includes at least one scanning area, and the light transmitting unit scans the at least one scanning area at at least one scanning rate.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of co-pending U.S. patent applicationSer. No. 15/771,924 filed Apr. 27, 2018, which is the National Phase ofPCT International Application No. PCT/KR2016/012232, filed on Oct. 28,2016, which claims priority under 35 U.S.C. 119(a) to Patent ApplicationNos. 10-2015-0150575, filed in the Republic of Korea on Oct. 28, 2015and 10-2016-0141697, filed in the Republic of Korea on Oct. 28, 2016,all of which are hereby expressly incorporated by reference into thepresent application.

TECHNICAL FIELD

Embodiments relate to an optical output module, a vehicle including thesame, and a control method therefor.

BACKGROUND ART

A light detection and ranging (LiDAR) measuring apparatus transmits abeam toward an object and receives a reverse beam that is reflected andreturned back by the objet to measure, examine, and analyze informationon a distance or position of the object.

FIG. 1 is a diagram showing an outer appearance of a general opticaloutput module 10.

As shown in FIG. 1, the general optical output module 10 may emit a beamemitted from a plurality of light sources (not shown) toward an objectin various directions using a motor (not shown) and receive a reversebeam using a detector.

In this case, a portion for emitting a plurality of beams 12 may berotated (see arrow 20) by a motor and may be mechanically moved and,thus, there may be various limits. That is, it may not be easy to ensuremechanical reliability of a motor portion and, due to use of a motor,there may be a limit in reducing a size of the optical output module 10and it may be difficult to ensure a scan rate of a specific region. Inaddition, there is a need for a plurality of light sources and detectorsto extend a measurement range in a vertical direction. A light receivingunit for a general optical output module requires a condensing lens and,thus, efficiency is degraded and there is a limit in acquiring variouspieces of information.

Recently, as interest in unmanned autonomous driving increases, anoptical output module according to exemplary embodiments has beeninstalled in a vehicle to realize unmanned autonomous driving of avehicle.

First, unmanned autonomous driving is a technology for autonomouslycontrolling steering, change of speed, acceleration, and brakingaccording to a surrounding environment based on a recognition apparatussuch as a sensor and a camera and an autonomous navigation apparatussuch as a global positioning system (GPS) module to autonomously driveto a destination.

In addition, unmanned autonomous driving is a technology used in manyfields such as a commercial field including an assistance device for thedisabled as well as the non-disabled, for military purposes, and forcargo transport.

For unmanned autonomous driving of a vehicle on an actual road, aposition, etc. of an obstacle positioned ahead or behind a drivingvehicle need to be determined.

There is a problem in that an optical output module installed and usedin a conventional vehicle is not capable of controlling a scan rate oris not capable of being appropriately driven according to a drivingsituation due to limitations of a driving method. For example, there isa problem in that, when a vehicle travels at high speed, distanceresolution of a region of interest is remarkably degraded and resolutionof position information, etc. of other vehicles positioned ahead isdegraded.

DISCLOSURE Technical Problem

Embodiments provide an optical output module and a vehicle for adjustingrotation speed of a detection direction in response to driving speed ofa vehicle by a vehicle light detection and ranging (LiDAR) measuringapparatus for collecting surrounding information by a camera deviceinstalled in the vehicle during driving and measuring information on anobject using a laser beam.

Further, embodiments provide an optical output module and a vehicle foreffectively acquiring information according to state information of adriving situation, etc. of the vehicle.

Technical Solution

In one embodiment, an optical output module includes a drivingcontroller and an optical transmitter configured to output light to scanthe scan region, wherein the optical transmitter scans the scan regionat at least one scan rate according to driving speed.

The scan region may include a high speed scan region and a low speedscan region, the high speed scan region may be positioned in a centralportion of the scan region, and the low speed scan region may be aregion obtained by excluding the high speed scan speed from the scanregion.

The optical transmitter may scan the scan region at a first scan ratewhen scanning the high speed scan region and scan the scan region at asecond scan rate when scanning the low speed scan region.

The first scan rate may be higher than the second scan rate.

The first scan rate may be equal to or greater than 15 Hz and the secondscan rate may be 1 Hz to 10 Hz.

A center angle of the high speed scan region may be equal to or greaterthan at least 70°.

In another embodiment, a vehicle includes a body configured to provide aspace with a user accommodated therein, and an optical output moduledisposed at a position adjacent to the body and configured to scansurrounding information of the body, wherein the optical output moduleincludes, an optical transmitter configured to discharge a plurality ofbeams to a scan region and to scan the scan region, and an opticalreceiver configured to measure information on an object using a reversebeam via a process in which the discharged beam is reflected andreturned back by the object positioned in the scan region, wherein thescan region includes at least one sub scan region, and wherein theoptical transmitter scans the scan region at at least one scan rateaccording to driving speed of the body.

The scan region may include a high speed scan region and a low speedscan region, the high speed scan region may be positioned in a centralportion of the scan region, and the low speed scan region may be aregion obtained by excluding the high speed scan speed from the scanregion.

The optical transmitter may scan the scan region at a first scan ratewhen scanning the high speed scan region and scan the scan region at asecond scan rate when scanning the low speed scan region.

The first scan rate may be higher than the second scan rate.

In another embodiment, a method of controlling an autonomous drivingvehicle including a light detection and ranging (LiDAR) measuringapparatus installed therein includes recognizing a rate of the vehicle,determining whether the rate of the vehicle is greater than apredetermined threshold rate, adjusting a scan rate when the rate of thevehicle is greater than the threshold value, and applying current topermit an optical output module in the LiDAR measuring apparatus toperform scanning at the adjusted scan rate.

The method may further include collecting information on the objectusing a reverse beam obtained by reflecting a beam discharged from theoptical output module off an object positioned in a scan region.

The scan region may include at least one sub scan region, and the scanrate in the sub scan region may be adjusted by the rate of the vehicle.

The rate of the vehicle may be directly measured through the opticaloutput module or may be provided from the vehicle.

In another embodiment, a light detection and ranging (LiDAR) measuringapparatus includes an optical transmitter configured to discharge aplurality of beams to a scan region to a scan region and to scan thescan region, and an optical receiver configured to measure informationon an object using a reverse beam via a process in which the dischargedbeam is reflected and returned back by the object positioned in the scanregion, wherein the scan region includes at least one sub scan region,and wherein the optical transmitter scans the at least one sub scanregion at at least one scan rate.

Advantageous Effects

According to exemplary embodiments, an entire scan region or a scanavailable region of a vehicle light detection and ranging (LiDAR)measuring apparatus may be split into at least one sub scan region inresponse to driving speed of the vehicle with the vehicle LiDARmeasuring apparatus installed therein and the at least one sub scanregion may be scanned at different rates (different speeds), therebyenhancing scanning resolution with respect to a region of interest inresponse to driving speed of a vehicle with an optical output moduleinstalled therein.

DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram showing an outer appearance of a general lightdetection and ranging (LiDAR) module.

FIG. 2 is a block diagram of a LiDAR module according to an exemplaryembodiment.

FIG. 3 is a block diagram of another exemplary embodiment of an opticalreceiver in an optical output module according to an exemplaryembodiment.

FIG. 4 is a diagram showing an optical output module installed a vehicleto measure LiDAR according to an exemplary embodiment.

FIG. 5 is a diagram showing an optical output module installed a vehicleto measure LiDAR according to another exemplary embodiment opticaloutput module.

FIG. 6 is a flowchart showing a method of controlling an optical outputmodule installed in a vehicle depending on a rate of the vehicleaccording to an exemplary embodiment.

BEST MODE

The present disclosure will now be described more fully with referenceto the accompanying drawings, in which exemplary embodiments of thepresent disclosure are shown. The present disclosure may, however, beembodied in many different forms and should not be construed as limitedto the exemplary embodiments set forth herein. Rather, these embodimentsare provided so that this disclosure will be thorough and complete, andwill fully convey the scope of the present disclosure to those skilledin the art.

The terms “first”, “second”, “on/upper/above”, and “under/lower/below”used herein are only used to distinguish one object or element fromanother object or element without requiring or including a physical orlogical relationship or order between objects or elements.

FIG. 2 is a block diagram of a light detection and ranging (LiDAR)measuring apparatus according to an exemplary embodiment.

A LiDAR module illustrated in FIG. 2 may include an optical transmitter110A, an optical receiver 120A, a sensing unit 130, and a drivingcontroller 140.

First, the optical transmitter 110A may emit one or more beams or aplurality of beams. Although FIG. 2 illustrates the case in which aplurality of beams is emitted according to the embodiment, one beam maybe emitted. To this end, the optical transmitter 110A may include afirst heat sink 111, at least one light source 112, a transmissionoptical system 114, and a beam steering unit 118. The opticaltransmitter 110A may further include a beam splitter 116.

The at least one light source 112 may emit light. When a centerwavelength of light emitted from the at least one light source 112 isgreater than 2 μm, the light is light and, thus, may not be appropriatefor light detection and ranging measurement. When a wavelength of lightemitted from the at least one light source 112 is less than 0.2 μm, thelight emitted from the optical transmitter 110A may be harmful to humansand may also be absorbed by impurities in the air while proceedingtoward an object (an object or a material) and, thus, may havedifficulty in reaching a distant object. Accordingly, a centerwavelength of light emitted from the at least one light source 112 maybe 0.2 μm to 2 μm but exemplary embodiments are not limited thereto.

Here, the object may float in the air or may be positioned on the groundor may be a particle that floats in the air. Exemplary embodiments arenot limited to a specific type of object.

Wavelength distribution of the at least one light source 112 may beequal to or less than 1 μm.

The at least one light source 112 may be a pulse type light source witha predetermined duty rate. On time of a pulse may be equal to or greaterthan 1 nm. A pulse type may be square wave, a triangular wave, asawtooth wave, a sine wave, a delta function, or a sine function (sincfunction). In addition, a pulse period may not be constant.

The at least one light source 112 may be a light source device with oneor more space modes. In this case, the space mode may be represented by‘n’ order of a Gaussian or Lambertian space mode, where n is equal to orgreater than 1.

The at least one light source 112 may be a light source devicerepresented by the sum of linear polarization or circular polarization.In this case, a ratio of polarization components may be represented as1:A based on one polarization component and A may be equal to or lessthan 1.

Although FIG. 2 illustrates only one light source 112, exemplaryembodiments are not limited thereto. According to another exemplaryembodiment, the number of the light sources 112 may be plural. When theat least one light source 112 includes a plurality of light sources,types of the plurality of light sources may be the same or different.

Heat generated from the at least one light source 112 may adverselyaffect an operation of the optical output module. Accordingly, the firstheat sink 111 may dissipate heat generated from the at least one lightsource 112. As necessary, the first heat sink 111 may be omitted.

The beam splitter 114 may split light emitted from the at least onelight source 112 into a first beam B1 and a second beam B2. The firstbeam B1 split by the beam splitter 114 may be dissipated toward thesplit first beam B1 and the second beam B2 may be discharged toward thebeam steering unit 118.

An intensity ratio between the first beam B1 and the second beam B2 ofthe light split by the beam splitter 114 may be K:1. For example, K maybe greater than 0 and less than 10.

The beam splitter 114 may include a device using at least one methodselected from linear polarization, circular polarization, a space modeof the light source 112, or a wavelength of the light source 112.

The beam splitter 114 may include at least one of a device for spatiallysplitting light or a device for temporally splitting light. The beamsplitter 114 may be omitted.

The transmission optical system 114 may be disposed between the at leastone light source 112 and the beam splitter 116 and, when the beamsplitter 114 is omitted, the transmission optical system 114 may bedisposed between a light source and the beam steering unit 118. Thetransmission optical system 114 may include a collimator 114A forcollimating light emitted from the at least one light source 112. Asnecessary, the transmission optical system 114 may be omitted.

The beam steering unit 118 may split the second beam B2 emitted from thebeam splitter 116 into a plurality of third beams B3 [B0, B(1−1), . . .B(1−N), B(2−1), . . . B(2−M)] and emit the third beams B3 in differentdirections. Here, N may be a positive integer equal to or greater than 1and M may be a positive integer equal to or greater than 1. The thirdbeams B3 will be described below in detail. When the beam splitter 116is omitted, the beam steering unit 118 may steer one beam.

According to the exemplary embodiment, the beam steering unit 118 mayinclude at least one transmission optical device. Although FIG. 2illustrates the case in which the beam steering unit 118 includes firstand second transmission optical devices S1 and S2, exemplary embodimentsare not limited thereto. That is, the beam steering unit 118 may includeonly one transmission optical device or two or more transmission opticaldevices. Hereinafter, although the case in which the beam steering unit118 includes the first and second transmission optical devices S1 and S2will be described, exemplary embodiments are not limited thereto.

The first and second transmission optical devices S1 and S2 may splitthe second beam B2 emitted from the beam splitter 116 into the pluralityof third beams B3 and emit the third beams B3 in different directions.When the beam splitter 116 is omitted, the first and second transmissionoptical devices S1 and S2 may receive and steer a single beam.

A plurality of beams emitted toward an object from the opticaltransmitter 110A may include the first beam B1 and the third beam B3.Each of the first and second transmission optical devices S1 and S2 mayemit the plurality of beams B1 and B3 toward an object in differentdirections without being mechanically rotated by a motor or the like.

The first and second transmission optical devices S1 and S2 may includeat least one lens. In this case, at least some lens S1 included in thetransmission optical device may be driven and, to drive the some lensS1, a beam emitted from the beam steering unit 118 may be steered.

Each of the first and second transmission optical devices S1 and S2 maysplit the second beam B2 into the plurality of third beams B3 indifferent directions and emit the third beams B3 in response to at leastone of an electrical signal, a physical signal, or a chemical signal.The electrical signal, the physical signal, or the chemical signal maybe provided from the driving controller 140 to the optical transmitter110A in the form of a first control signal C1. That is, an externalstimulus may be present, at least one of the electrical signal, thephysical signal, or the chemical signal may be generated as the firstcontrol signal C1 from the driving controller 140 by the stimulus, and atraveling path (i.e., an emission angle) of the plurality of third beamsB3 emitted from each of the first and second transmission opticaldevices S1 and S2 may be determined according to the generated firstcontrol signal C1.

Each of the first and second transmission optical devices S1 and S2 maybe embodied as a transmission optical phased array (OPA). Thetransmission OPA may generate the plurality of third beams B3 to beemitted in different directions from the second beam B2 split by thebeam splitter 116.

Each of the first and second transmission optical devices S1 and S2embodied as a transmission OPA may be embodied in various followingmethods.

First, each of the first and second transmission optical devices S1 andS2 may have a surface on which a diffraction grating is periodicallyformed. In this case, when at least one of a grating period, angle, orshape is changed, the first and second transmission optical devices S1and S2 may generate the plurality of third beams B3 to be emitted indifferent directions.

The first and second transmission optical devices S1 and S2 may haverespective internal structures with a periodically changed refractiveindex difference. In this case, when a period is changed or a refractiveindex is changed, the first and second transmission optical devices S1and S2 may generate the plurality of third beams B3 to be emitted indifferent directions.

Each of the first and second transmission optical devices S1 and S2 mayhave a polarization grating structure for periodic on/off ofpolarization using liquid crystal. In this case, when at least one of aninterval or transmittance of a grating is adjusted, the first and secondtransmission optical devices S1 and S2 may generate the plurality ofthird beams B3 to be emitted in different directions.

Each of the first and second transmission optical devices S1 and S2 maybe configured in the form of a double refraction prism. In this case,when an angle of a prism is changed, the first and second transmissionoptical devices S1 and S2 may generate the plurality of third beams B3to be emitted in different directions.

Each of the first and second transmission optical devices S1 and S2 mayhave a structure with a boundary surface between air and liquid such asoil. In this case, when a signal is externally applied to change theboundary surface or a refractive index of liquid is changed, the firstand second transmission optical devices S1 and S2 may generate theplurality of third beams B3 to be emitted in different directions.

When a refractive index or density distribution pattern in a medium ischanged using a hologram method, the first and second transmissionoptical devices S1 and S2 may generate the plurality of third beams B3to be emitted in different directions.

Each of the first and second transmission optical devices S1 and S2 mayhave a structure with transmittance that is periodically changeddepending on intensity of liquid crystal. In this case, when a period ischanged or transmittance is changed, the first and second transmissionoptical devices S1 and S2 may generate the plurality of third beams B3to be emitted in different directions.

Each of the first and second transmission optical devices S1 and S2 mayhave a microelectromechanical system (MEMS) mirror array. In this case,when an operation state of each pixel is controlled, the first andsecond transmission optical devices S1 and S2 may generate the pluralityof third beams B3 to be emitted in different directions.

When an ultrasonic wave is injected into a medium and a frequency of theultrasonic wave is changed, the first and second transmission opticaldevices S1 and S2 may generate the plurality of third beams B3 to beemitted in different directions.

Each of the first and second transmission optical devices S1 and S2 mayhave a medium in which an electric field is formed in up, down, right,and left directions. In this case, when the intensity and frequency ofan electric field is changed, the first and second transmission opticaldevices S1 and S2 may generate the plurality of third beams B3 to beemitted in different directions.

Each of the first and second transmission optical devices S1 and S2 mayhave two or more aligned lens sets. In this case, when a separate lensof the lens set is moved in up, down, right, and left directions, thefirst and second transmission optical devices S1 and S2 may generate theplurality of third beams B3 to be emitted in different directions.

Each of the first and second transmission optical devices S1 and S2 mayhave two or more aligned microlens array (MLA) sets. In this case, whena separate MLA is moved in up, down, right, and left directions, thefirst and second transmission optical devices S1 and S2 may generate theplurality of third beams B3 to be emitted in different directions.

Each of the first and second transmission optical devices S1 and S2 mayhave two or more aligned microlens array (MLA) sets. In this case, whenthe period or shape of a separate MLA is changed, the first and secondtransmission optical devices S1 and S2 may generate the plurality ofthird beams B3 to be emitted in different directions.

To permit the aforementioned various transmission optical devices toemit light in different directions, a width range within which theaforementioned period (or a pattern such as a surface) is changed may be0.1 μm to 2 μm, in the case of a wavelength of 1000 nm, a range withinwhich the aforementioned refractive index is changed may be greater than1 and less than 2.7, and a range within which the aforementionedtransmittance and reflectivity are changed may be greater than 0 andless than 1 but exemplary embodiments are not limited thereto.

The aforementioned various transmission optical devices may be complexlycombined and may generate the plurality of third beams B3 to be emittedin different directions.

To operate each of the first and second transmission optical devices S1and S2 with the aforementioned various structures, an electrical signalmay be applied to opposite ends of each of the first and secondtransmission optical devices S1 and S2. In this case, the electricalsignal may be a periodic voltage signal or a current signal. Forexample, an operational frequency of the electrical signal may be equalto or less than 10 GHz.

To operate each of the first and second transmission optical devices S1and S2 with the aforementioned various structures, physical pressure maybe applied to the first and second transmission optical devices S1 andS2 or a physical position of the first and second transmission opticaldevices S1 and S2 may be changed. In this case, the physical position ofthe first and second transmission optical devices S1 and S2 may be movedin an optical axis direction or moved along two axes perpendicular tothe optical axis direction. To this end, a magnetic field may be used, apiezoelectric (PZT) device may be used, a voice coil motor (VCM) may beused, a link structure may be used, or gravity and elasticity may beused.

The plurality of third beams B3 emitted from the first and secondtransmission optical devices S1 and S2, which embody the beam steeringunit 118, may include at least one of a 0th beam BO emitted in anoptical axis direction, N(1−1)th to (1−N)th beams B(1−1), . . . B(1−N)emitted to be spaced apart from each other counterclockwise from theoptical axis direction, or M(2−1)th to (2−M)th beams B(2−1), . . .B(2−M) emitted to be spaced apart from each other clockwise from theoptical axis direction.

The plurality of third beams B3 B0, B(1−1), . . . B(1−N), B(2−1), . . .B(2−M) may be emitted to be spaced apart from each other. The (1−1)th to(1−N)th beams B(1−1), . . . B(1−N) and (2−1)th to (2−M)th beams B(2−1),. . . B(2−M) may be emitted to be spaced apart from each other at apredetermined angle with the 0th beam BO. For example, the (1−1)th beamB(1−1) may be spaced apart from the 0th beam BO at a (1−1)th angleθ(1−1)T, the (1−N)th beam B(1−N) may be spaced apart from the 0th beamBO at a (1−N)th angle θ(1−N)T, the (2−1)th beam B(2−1) may be spacedapart from the 0th beam BO at a (2−1)th angle θ(2−1)T, and the (2−M)thbeam B(2−M) may be spaced apart from the 0th beam BO at an (2−M) angleθ(2−M)T.

Among angles at which the plurality of third beams B3 are spaced apartfrom each other, the (1−N)th or (2−M)th beams B(1−N) and B(2−M) may bespaced apart from the 0th beam BO by the largest angle. The largestangle θ(1−N)T or θ(2−M)T may be less than 90° but exemplary embodimentsare not limited thereto.

An angle at which neighboring beams are spaced apart from each otheramong 0th, (1−1)th to (1−N)th and (2−1)th to (2−M)th beams BO, B(1−1), .. . B(1−N), B(2−1), . . . B(2−M) may be less than 200 but exemplaryembodiments are not limited thereto.

The optical receiver 120A may receive a plurality of reverse beams,obtained via a process in which one beam or the plurality of beams B1and B3 emitted from the optical transmitter 110A are reflected by anobject (not shown), at different angles and, measure (examine oranalyze) information on the object using the plurality of receivedreverse beams.

According to the exemplary embodiment, the optical receiver 120A mayinclude a second heat sink 121, an optical inspector 122, an opticaldetector 124, a filter 126A, and a reception optical system 128. Theoptical detector 124 may be omitted from the optical receiver 120A.

The optical detector 124 may receive a plurality of reverse beams RBs,which are reflected and returned back by an object, at different anglesand transmit the reverse beams RBs to the optical inspector 122 at apredetermined angle.

The reverse beams RBs incident on the optical detector 124 may includeat least one of a 0th reverse beam RO that is incident in an opticalaxis direction, i(1−1)th to (1−i)th reverse beams R(1−1), . . . R(1−i)that are spaced apart from each other counterclockwise from an opticalaxis direction and are incident on, or j(2−1)th to (2−j)th reverse beamsR(2−1), . . . R(2−j) that are spaced apart clockwise from the opticalaxis direction and are incident. Here, i may be a positive integer equalto or greater than 1 and j may be a positive integer equal to or greaterthan 1.

Each of the (1−1)th to (1−i)th reverse beams R(1−1), . . . R(1−i) andthe (2−1)th to (2−j)th reverse beams R(2−1), . . . R(2−j) may be spacedapart from a 0th reverse beam RO at a predetermined angle. For example,the (1−1)th reverse beam R(1−1) may be spaced apart from the 0th reversebeam RO at a (1−1)th angle θ(1−1)R, the (1−i)th reverse beam R(1−i) maybe spaced apart from the 0th reverse beam RO at the (1−i)th angleθ(1−i)R, the (2−1)th reverse beam R(2−1)th may be spaced apart from the0th reverse beam RO at the (2−1)th angle θ(2−1)R, and the (2−j)threverse beam R(2−j) may be spaced apart from the 0th reverse beam RO atthe (2−j)th θ(2−j)R. As such, the plurality of reverse beams R0, R(1−1),. . . R(1−i), R(2−1), . . . R(2−j) may be spaced apart from each otherand may be incident on the optical detector 124.

The optical detector 124 may include at least one reception opticaldevice. Although FIG. 2 illustrates the case in which the opticaldetector 124 includes first and second reception optical devices D1 andD2, exemplary embodiments are not limited thereto. That is, according toother exemplary embodiments, the optical detector 124 may include onlyone reception optical device or may include three or more receptionoptical devices. Like the transmission optical devices S1 and S2, thereception optical devices D1 and D2 may be operated in response to atleast one of an electrical signal, a physical signal, or a chemicalsignal. The electrical signal, the physical signal, or the chemicalsignal may be provided from the driving controller 140 to the opticalreceiver 120A in the form of a second control signal C2. That is, anexternal stimulus may be present, at least one of the electrical signal,the physical signal, or the chemical signal may be generated as thesecond control signal C2 from the driving controller 140 by thestimulus, and each of the first and second reception optical devices D1and D2 may adjust at least one of transmittance or reflectivity by thegenerated second control signal C2.

Each of the first and second reception optical devices D1 and D2 may beembodied as a reception OPA. The reception OPA may emit a plurality ofreverse beams at different angles to output the beams at a constantangle. Each of the first and second reception optical devices D1 and D2embodied as a reception OPA may be operated using various followingmethods.

First, each of the first and second reception optical devices D1 and D2may have a surface on which a diffraction grating is periodicallyformed. In this case, when at least one of a grating period, angle, orshape is changed, each of the first and second reception optical devicesD1 and D2 may be operated.

The first and second transmission optical devices S1 and S2 may haverespective structures with a periodically changed refractive indexdifference. In this case, when a period is changed or a refractive indexis changed, each of the first and second reception optical devices D1and D2 may be operated.

Each of the first and second reception optical devices D1 and D2 mayhave a double refraction prism. In this case, when an angle of the prismis changed, each of the first and second reception optical devices D1and D2 may be operated.

Each of the first and second reception optical devices D1 and D2 mayhave a structure with a boundary surface between air and liquid such asoil. In this case, when a signal is externally applied to change theboundary surface or a refractive index of liquid is changed, each of thefirst and second reception optical devices D1 and D2 may be operated.

When a refractive index or density distribution pattern in a medium ischanged using a hologram method, each of the first and second receptionoptical devices D1 and D2 may be operated.

Each of the first and second reception optical devices D1 and D2 mayhave two or more lens sets. In this case, when a separate lens of thelens set is moved in up, down, right, and left directions, each of thefirst and second reception optical devices D1 and D2 may be operated.

Each of the first and second reception optical devices D1 and D2 mayhave two or more aligned microlens array (MLA) sets. In this case, whena separate MLA is moved in up, down, right, and left directions, each ofthe first and second reception optical devices D1 and D2 may beoperated.

Each of the first and second reception optical devices D1 and D2 mayhave two or more aligned microlens array (MLA) sets. In this case, whenat least one of the period or shape of a separate MLA is changed, eachof the first and second reception optical devices D1 and D2 may beoperated.

To operate the aforementioned various reception optical devices, a widthrange within which the aforementioned period (or a pattern such as asurface) is changed may be 0.1 μm to 2 mm, in the case of a wavelengthof 1000 nm, a range within which the aforementioned refractive index ischanged may be greater than 1 and less than 2.7, and a range withinwhich the aforementioned transmittance and reflectivity are changed maybe greater than 0 and less than 1 but exemplary embodiments are notlimited thereto.

The optical detector 124 may multiply include the reception opticaldevice that is operated in various ways as described above.

To operate the first and second reception optical devices D1 and D2 withvarious structures as described above, an electrical signal may beapplied to opposite ends of each of the first and second receptionoptical devices D1 and D2. In this case, the electrical signal may be aperiodic voltage signal or current signal. For example, an operationrate of the electrical signal may be equal to or less than 10 GHz.

To operate the first and second reception optical devices D1 and D2 withvarious structures as described above, physical pressure may be appliedto the first and second reception optical devices D1 and D2 and aphysical position of the first and second reception optical devices D1and D2 may be changed. In this case, the physical position of the firstand second reception optical devices D1 and D2 may be moved in anoptical axis direction or moved in two-axis directions perpendicular tothe optical axis direction. To this end, a magnetic field may be used, apiezoelectric (PZT) device may be used, a voice coil motor (VCM) may beused, a link structure may be used, or gravity and elasticity may beused.

An angle at which a reverse beam is incident may be adjusted usingvarious methods. For example, the (1−i)th or (2−j)th reverse beamsR(1−i) and R(2−j) may be spaced apart from the 0th beam BO by thelargest angle. The largest angle θ(1−i)R or θ(2−j)R may be less than 90°but exemplary embodiments are not limited thereto.

An angle between adjacent beams among 0th, (1−1)th to (1−i)th and(2−1)th to (2−j)th beams RO, R(1−1), . . . R(1−i), R(2−1), . . . R(2−j)may be set to be less than 20° but exemplary embodiments are not limitedthereto.

The reception optical system 128 may be disposed between the opticalinspector 122 and the optical detector 124 and may focus light emittedfrom the optical detector 124 to provide the light to the opticalinspector 122. To this end, the reception optical system 128 may includea collector 128A but exemplary embodiments are not limited thereto. Asnecessary, the reception optical system 128 may be omitted.

FIG. 3 is a block diagram of another exemplary embodiment 120B of anoptical receiver in an optical output module according to an exemplaryembodiment.

An optical receiver 120B illustrated in FIG. 3 may include the secondheat sink 121, the optical inspector 122, the optical detector 124, afilter 126B, and the reception optical system 128. Except that the formof the filter 126B is different from the filter 126A illustrated in FIG.2, the optical receiver 120B illustrated in FIG. 3 may be the same asthe optical receiver 120A illustrated in FIG. 2.

The filters 126A and 126B may be disposed between the optical detector124 and the reception optical system 128, may selectively filter atleast one wavelength required by a reverse beam emitted from the opticaldetector 124 or remove noise, and may pass or reflect and provide theresult to the optical inspector 122. The transmissive filter 126A shownin FIG. 2 may selectively pass and filter a desired wavelength and, onthe other hand, the reflective filter 126A shown in FIG. 3 mayselectively reflect and filter a desired wavelength.

As necessary, the filters 126A and 126B may be omitted.

A reception OPA outputs reverse beams that are incident at differentangles, at a constant angle and, thus, the transmission or reflectionefficiency of the filters 126A and 126B may be enhanced.

A wavelength range filtered by the filters 126A and 126B may be one orplural.

A range of a center wavelength of at least one wavelength filtered bythe filters 126A and 126B may be 0.2 μm to 2 μm and a bandwidth of afiltered wavelength may be 1 nm or greater. When a ratio of intensity ofa wavelength interrupted by the filters 126A and 126B and intensity of aselected wavelength is F:1, F may be equal to or less than 0.5.

A filter optical device having at least one central angle of incidentlight with maximum transmission efficiency of the filter 126A or maximumreflection efficiency of the filter 126B may be included. Here, thefilter optical device may be embodied in various forms.

For example, filter optical devices 126-1 and 126-2 may be configured insuch a way that two or more thin films with two or more refractiveindexes are stacked. In addition, the filter optical device may beembodied in such a way that a grating structure is formed on a surfaceof the filter optical device to adjust a refractive or reflective angleof a specific wavelength. Alternatively, the filter optical device maybe configured to select a specific wavelength by periodically changingan internal refractive index.

Light with a wavelength selected by the filters 126A and 126B may bepassed or reflected and transmitted to the optical inspector 122. Inthis case, when the filter 126A is a transmissive filter for passinglight and transmitting the light to the optical inspector 122, if anincident angle of light incident on the transmissive filter 126A isequal to or less than 60°, transmission efficiency of the filter 126Amay be maximized. In addition, when the filter 126B is a reflectivefilter for reflecting light and transmitting the light to the opticalinspector 122, if an angle of light incident on the reflective filter126B is equal to or greater than 25°, reflection efficiency of thefilter 126B may be maximized.

The second heat sink 121 may dissipate heat emitted from the opticalinspector 122 and, as necessary, may be omitted.

The optical inspector 122 may measure (or analyze) information on anobject from a reverse beam that is provided through the filters 126A and126B from the optical detector 124.

The optical inspector 122 may measure a time difference between aplurality of beams emitted from the optical transmitter 110A and areverse beam output from the optical detector 124. To this end,intensity of a reverse beam, obtained via a process in which a pluralityof beams B1 and B3 emitted from the optical transmitter 110A isreflected and returned back by an object, may be converted into anelectrical signal. In addition, intensity of a reverse beam, obtainedvia a process in which the plurality of beams B1 and B3 emitted from theoptical transmitter 110A is reflected by the object, may be convertedinto an electrical signal in a time sequence. In this case, the opticalinspector 122 may measure a time difference between a plurality of beamsand a reverse beam using the electrical signal.

The optical inspector 122 may measure a time difference based on a timepoint when some of light emitted from the optical transmitter 110A isfirst measured. In addition, the optical inspector 122 may measure atime difference based on an electrical signal synchronized with theoptical transmitter 110A.

One or plural light receiving units are arranged in the form of aone-dimensional or two-dimensional array to embody the optical inspector122. In this case, a time difference of light reflected at apredetermined position may be measured using a plurality of lightreceiving units. Alternatively, a spatial difference of signals or atime difference between spaces may be measured through a plurality oflight receiving units. In this case, a received signal for each pixel ofan array may be distinguished and converted into an electrical signal.For example, the light receiving unit may use an avalanche photodiode(APD), a single photon avalanche photodiode (SPAPD), a single avalanchephotodiode (SAPD), a photodiode (PD), a quantum well photodiode (QWP), aphoto multiplying tube (PMT), or the like.

The optical inspector 122 may simultaneously measure a time differenceand a spatial position between reverse obtained via a process in whichlight transmitted from the optical transmitter 110A is reflected andreturned back by an object.

The optical inspector 122 may analyze information on an object using atleast one of intensity of a reverse beam or a spatial position of theobject. Here, information on the inspected object may include, forexample, at least one of distance or position information of the object.

The optical inspector 122 may measure basic data for measuringinformation on an object and transmit the measurement result to ananalysis unit (not shown). In this case, the analysis unit may analyzeinformation on the object using the basic data measured by the opticalinspector 122.

The aforementioned optical output module according to an exemplaryembodiment may further include a first housing H1. The first housing H1may be shaped to surround the optical transmitter 110A and the opticalreceiver 120A. However, the first housing H1 may be omitted.

The driving controller 140 may control at least one of the opticaltransmitter 110A or the optical receiver 120A. That is, the drivingcontroller 140 may generate an electrical signal, a physical signal, ora chemical signal in the form of the first and second control signals C1and C2 and control driving of the transmission optical devices S1 and 32and the reception optical devices D1 and D2 according to the first andsecond control signals C1 and C2.

Here, each of the first and second control signals C1 and C2 generatedby the driving controller 140 may take the form of a continued wave (CW)or a continued pulse and exemplary embodiments are not limited to aspecific form of the first and second control signals C1 and C2.

The sensing unit 130 may sense the first beam B1 split by the beamsplitter 116 and transmit the sensing result to the driving controller140. In this case, the driving controller 140 may generate the first andsecond control signals C1 and C2 using the sensing result received fromthe sensing unit 130 and control the optical transmitter 110A and theoptical receiver 120A using the generated first and second controlsignals C1 and C2.

For the aforementioned operation, the sensing unit 130 may include aphotodiode 132 and a sensing optical system 134. The photodiode 132 maysense the first beam B1 split by the beam splitter 116, convert thefirst beam B1 into an electrical signal, and output the convertedelectrical signal as the sensing result to the driving controller 140.

The sensing optical system 134 may be arranged between the split firstbeam B1 and the photodiode 132. To this end, the sensing optical system134 may include, for example, a plurality of prisms 134-1 and 134-2 butexemplary embodiments are not limited thereto.

As described above, the optical transmitter 110A and the opticalreceiver 120A may be controlled using the first beam B1 split by thebeam splitter 116 and, thus, the accuracy of a value that is lastlyinspected by the optical inspector 122 may be enhanced. For example, asan analysis result of the sensing result of the sensing unit 130, whenintensity of the first beam B1 is determined to be weak, intensity ofthe second beam B2 may be estimated to be weak. Accordingly, to increaseintensity of the second beam B2, the driving controller 140 may increaseintensity of light emitted from the light source 112 by a desireddegree. Accordingly, intensity of the plurality of beams B1 and B3 isweak and, thus, intensity of a plurality of reverse beams received bythe optical receiver 120A and 120B is weak, thereby overcoming a problemin that information on an object is not capable of being accuratelyanalyzed.

The aforementioned optical output module according to an exemplaryembodiment may further include a second housing H2. The second housingH2 may be shaped to surround the sensing unit 130. However, the secondhousing H2 may be omitted.

According to an exemplary embodiment, a plurality of beams emitted to anobject may include the first beam B1 as well as the third beam B3.Accordingly, a direction of a beam emitted to an object may be extendedcompared with a conventional case. Such extension of a direction of abeam is described below with reference to the accompanying drawings.

Recently, as interest in unmanned autonomous driving increases, anoptical output module according to exemplary embodiments has beeninstalled in a vehicle to realize unmanned autonomous driving of avehicle.

First, unmanned autonomous driving is a technology for autonomouslycontrolling steering, change of speed, acceleration, and brakingaccording to a road environment based on an obstacle recognitionapparatus such as a sensor and a camera and an autonomous navigationapparatus such as a global positioning system (GPS) module toautonomously drive to a destination without a driver.

Unmanned autonomous driving is a technology used in many fields such asa commercial field including an assistance device for the disabled aswell as the non-disabled, for military purposes, and for cargotransport.

For unmanned autonomous driving of a vehicle on an actual road, aposition of another vehicle positioned ahead or behind a driving vehicleand surrounding information including an obstacle, etc. need to berecognized and determined.

An optical output module installed and used in a conventional vehicledoes not consider a scan rate according to a vehicle driving situation.For example, when a vehicle travels at high speed, if the vehicle hasthe same scan rate as in the case in which the vehicle travels at lowspeed, an optical output module installed in the vehicle is movedtherewith in response to driving speed and, thus, there is a problem inthat distance resolution is remarkably reduced, degrading resolution ofsurrounding information of an obstacle or a position of another vehiclepositioned ahead or behind the vehicle.

Exemplary embodiments may provide an optical output module forovercoming the aforementioned problem, which is described below indetail with reference to FIGS. 4 and 5.

With regard to configuration of light detection and ranging (LiDAR), anapparatus that is selectively driven at the same frame rate or at avariable rate according to a region of interest during 1D (line) or 2D(horizontal/vertical) output is described in detail.

FIG. 4 is a diagram showing an optical output module installed in avehicle to measure LiDAR according to an exemplary embodiment. FIG. 5 isa diagram showing an optical output module installed a vehicle tomeasure LiDAR according to another exemplary embodiment optical outputmodule.

FIG. 4 illustrates an optical output module when a vehicle travels atlow speed according to an exemplary embodiment. When the optical outputmodule according to the exemplary embodiment scans a front side of thevehicle at a first scan rate A when the vehicle travels at low speed andscans a region in which a center angle based on a center of the vehiclehas a first scan angle θ1.

Here, a scan rate of a specific region detected by a LiDAR measuringapparatus for a vehicle may be a time period in which a beam output froman optical output module stays in the specific region or a frequency ofscanning the specific region.

The first scan rate A may be a rate with sufficient resolution when avehicle travels at a threshold value (VC) or less while travelling atlow speed.

For example, the first scan rate A may be 1 Hz to 35 Hz and may beconfigured to have the same value in a range of the first scan angle θ1.

The first scan angle θ1 may be an angle at which a vehicle is capable ofrecognizing another vehicle that travels ahead or behind the vehicle.

For example, the first scan angle θ1 may be 70° or greater.

FIG. 5 is a diagram showing an optical output module when a vehicletravels at high speed according to an exemplary embodiment. When thevehicle travels at a threshold rate (VC) or greater while traveling athigh speed, a higher scan rate than the first scan rate A as a scan ratein the aforementioned case in which the vehicle travels at low speed maybe provided.

The optical output module may collect information on an object using aplurality of reverse beams obtained via a process in which light emittedfrom an optical transmitter is reflected and returned back by an objectand, in this regard, there is a problem in that it is not possible toscan the first scan angle θ1 for scanning in the case in which thevehicle travels at high speed equal to or greater than the thresholdrate (VC), at a higher scan rate (e.g., higher speed).

Accordingly, to prevent resolution from being degraded, when a vehicletravels at high speed, it may be necessary to operate the vehicle at ahigh scan rate different from the case in which the vehicle travels atlow speed. However, a range of a scan rate for operating a vehicle LiDARmeasuring apparatus may be limited and a scan rate may be increased inresponse to driving speed of the vehicle but there may be a limit inincreasing a scan rate in all regions. Accordingly, the vehicle LiDARmeasuring apparatus may selectively collect surrounding information foreach surrounding region of the vehicle in response to surrounding speedof the vehicle.

In particular, when a vehicle travels at high speed, information to bereceived from a front side may be more important than a lateral side ofthe vehicle compared with the case in which the vehicle travels at lowspeed. Accordingly, as a scan rate for collecting front informationbased on a driving direction of the vehicle in a vehicle that travels athigh speed is increased, vehicle running stability based on informationcollected through a vehicle LiDAR measuring apparatus may be enhanced.

A scan angle of the optical output module according to an exemplaryembodiment may be the first scan angle θ1 like in the case in which avehicle travels at low speed.

The first scan angle θ1 may include a second scan angle θ2 as a centerangle of a region to be scanned at a high scan rate and a third scanangle θ3 as a center angle to be scanned at a low scan rate.

One or two or more third scan angles 93 may be present.

In other words, a center angle of a high speed scan region in which highspeed scan is performed at a high scan rate may be the second scan angleθ2 and a center angle of a low speed scan region in which low speed scanis performed at a relatively low speed may be one or two or more thirdscan angles θ3.

The high speed scan region may be positioned at a central portion of anentire scan region and the low speed scan region may be positioned atopposite sides except for the high speed scan region in the entire scanregion. However, this is merely an exemplary embodiment, the exemplaryembodiment is not limited thereto, and low and high speed scan regionsmay be set in different forms.

That is, the sum of a second scan region as a high speed scan region anda third scan region as a low speed scan region may be the same as anentire scan region, a central angle of which is the first scan angle θ1.

Exemplary embodiments are not limited to the case in which a low scanregion is positioned at opposite sides, when a region of interest isgenerated, the generated region of interest may be set to a high speedscan region and driven at a high scan rate, and a portion except for theregion of interest may be set to a low speed scan region and driven at alower scan rate than the high speed scan region.

The optical output module according to an exemplary embodiment mayperform scanning at a second scan rate B in a high speed scan region andperform scanning at a third scan rate C in a low sped scan region.

That is, the second scan rate for scanning the high speed scan regionand the third scan rate for scanning the low speed scan region may bedifferent.

For example, the second scan rate B may be equal to or greater than 20Hz.

The third scan rate C may be used to scan a low speed scan region and,thus, may be less than the second scan rate B.

For example, the third scan rate C may be 1 Hz to 10 Hz.

However, the second scan rate B and the third scan rate C are an examplefor convenience of description and may be changed in various ways asnecessary and, a scope of the present disclosure is not limited as longas the second scan rate B is greater than the third scan rate C.

Hereinafter, a method of controlling an optical output module dependingon a rate of a vehicle during vehicle driving according to an exemplaryembodiment is described.

FIG. 6 is a flowchart showing a method of controlling an optical outputmodule installed in a vehicle depending on a rate of the vehicleaccording to an exemplary embodiment.

Referring to FIG. 6, first, the optical output module according to anexemplary embodiment may measure a rate of a vehicle in which theoptical output module is installed (Sl00).

Vehicle driving speed (rate) may be measured using various devices andthis would be obvious to one of ordinary skill in the art and, thus, themethod and configuration of measuring a vehicle rate are not described.For example, a vehicle LiDAR measuring apparatus may directly detectdriving speed of the vehicle and receive the driving speed of thevehicle from a vehicle in which the vehicle LiDAR measuring apparatus isinstalled.

A vehicle rate is measured (S100) and, then, whether the vehicle rate isgreater than a current rate VC may be determined (S200).

When the current rate of the vehicle is greater than the threshold rateVC, current driving may be determined as high speed driving and the scanrate may be corrected (S300), and current may be applied to an actuator,for example, the beam steering unit 118 (S400).

That is, as described, when a vehicle travels at high speed, an entirescan region may be divided into a high speed scan region and a low speedscan region and may be changed to provide rapid response with respect toa region of interest (i.e., a surrounding region that becomes importantin response to vehicle driving speed).

When the current rate of the vehicle is less than the threshold rate(VC), the current driving may be determined as low speed driving and anentire scan region may be scanned at a constant rate without correctionof a scan rate.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

1. An optical output module, comprising: an optical transmitterconfigured to output light to scan a scan region, wherein the opticaltransmitter is configured to be installed on a vehicle and the opticaltransmitter scans the scan region at at least one scan rate according toa driving speed of the vehicle, wherein the scan region comprises afirst speed scan region and a second speed scan region, wherein thefirst speed scan region is a region generated by a region of interest ofthe scan region, wherein the second speed scan region is a regionobtained by excluding the first speed scan region from the scan region,wherein the optical transmitter scans the scan region at a first scanrate when scanning the first speed scan region and scans the scan regionat a second scan rate when scanning the second speed scan region,wherein the first scan speed is faster than the second scan speed,wherein the first scan rate is higher than the second scan rate, andwherein the region of interest is the scan region that requires a rapidresponse in the scan region according to the driving speed of vehicle.2. The optical output module according to claim 1, wherein the sum ofthe first speed scan region and the second speed scan region is the sameas the scan region.
 3. The optical output module according to claim 1,wherein the first scan rate is equal to or greater than 20 Hz and thesecond scan rate is 1 Hz to 10 Hz.
 4. The optical output moduleaccording to claim 1, wherein a center angle of the first speed scanregion is equal to or greater than at least 70°.
 5. A vehiclecomprising: a body configured to provide a space with a useraccommodated therein; and an optical output module disposed at aposition adjacent to the body and configured to scan surroundinginformation of the body, wherein the optical output module comprises: anoptical transmitter configured to discharge a plurality of beams to ascan region and to scan the scan region; and an optical receiverconfigured to measure information on an object using a reverse beamobtained via a process in which the discharged beam is reflected andreturned back by the object positioned in the scan region, wherein thescan region comprises at least one sub scan region, wherein the opticaltransmitter scans the scan region at at least one scan rate according todriving speed of the body, wherein the scan region comprises a firstspeed scan region and a second speed scan region, wherein the firstspeed scan region is a region generated by a region of interest of thescan region, wherein the second speed scan region is a region obtainedby excluding the first speed scan region from the scan region, andwherein the first scan speed is faster than the second scan speed,wherein the first scan rate is higher than the second scan rate, andwherein the region of interest is the scan region that requires a rapidresponse in the scan region according to the driving speed of vehicle.6. The vehicle according to claim 5, wherein the sum of the first speedscan region and the second speed scan region is the same as the scanregion.
 7. The vehicle according to claim 5, wherein the opticaltransmitter scans the scan region at a first scan rate when scanning thefirst speed scan region and scans the scan region at a second scan ratewhen scanning the second speed scan region.
 8. A method of controllingan autonomous driving vehicle comprising a light detection and ranging(LiDAR) measuring apparatus installed therein, the method comprising:recognizing a speed of the vehicle; determining whether the speed of thevehicle is greater than a predetermined threshold speed; adjusting ascan rate of the LiDAR when the speed of the vehicle is greater than thethreshold value; applying current to permit an optical output module inthe LiDAR measuring apparatus to perform scanning at the adjusted scanrate; and controlling the vehicle based on the scanning at the adjustedscan rate, wherein adjusting the scan rate of the LiDAR includesscanning at a first scan rate when scanning a first speed scan regionand scanning at a second scan rate when scanning a second speed scanregion, and wherein the second speed scan region is different than thefirst speed scan region.
 9. The method according to claim 8, furthercomprising collecting information on an object positioned in a scanregion using a reverse beam obtained by reflecting a beam dischargedfrom the optical output module off the object.
 10. The method accordingto claim 9, wherein the scan rate is adjusted by the speed of thevehicle.
 11. The method according to claim 8, wherein the rate of thevehicle is directly measured through the optical output module or isprovided from the vehicle.
 12. A light detection and ranging (LiDAR)measuring apparatus comprising: an optical transmitter configured todischarge a plurality of beams to a scan region and to scan the scanregion; and an optical receiver configured to measure information on anobject using a reverse beam obtained via a process in which thedischarged beam is reflected and returned back by the object positionedin the scan region, wherein the scan region comprises at least one subscan region, wherein the optical transmitter scans the at least one subscan region at at least one scan rate, wherein the scan region comprisesa first speed scan region and a second speed scan region, wherein thefirst speed scan region is a region generated by a region of interest ofthe scan region, wherein the second speed scan region is a regionobtained by excluding the first speed scan region from the scan region,wherein the first scan speed is faster than the second scan speed,wherein the first scan rate is higher than the second scan rate, andwherein the region of interest is the scan region that requires a rapidresponse in the scan region according to the driving speed of vehicle.